Dosage regime with esketamine for treating major depressive disorder

ABSTRACT

The present invention provides a method for safe and efficacious administration of esketamine.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to U.S. ProvisionalApplication No. 62/954,779, filed Dec. 30, 2019, the entire contents ofwhich are incorporated herein by reference.

FIELD OF THE INVENTION

The present disclosure provides methods for safe and efficaciousadministration of esketamine.

BACKGROUND OF THE INVENTION

Ketamine is a non-barbiturate, rapid acting, induction and generalanesthetic agent that acts primarily via NMDA receptor antagonism in theCNS. The drug has been available in the United States since 1970 underthe tradename Ketalar®. In 1971, DE2062620 described ketamine's (-)enantiomer, esketamine. Esketamine is not approved for use in the UnitedStates but is available in Europe as an induction and general anestheticagent under the tradename Ketanest® S.

Sofia et al (1975) proposed the use of oral ketamine to treatdepression. Berman et al (1980) described the results of a placebocontrolled clinical trial of a single intravenous dose of ketamine in 7patients with major depression. DE102007009888 suggests the use of(S)(+)-ketamine in the treatment of depression. More recently, there hasbeen an increased interest in the possibility of using ketamine oresketamine for the treatment of major depressive disorder (MDD)including when the depression has proved refractory to other therapies.

Pharmaceutical compositions of ketamine and esketamine have beenadministered to healthy subjects and patients via a variety of roots ofadministration including intravenously, intranasally and orally.Clements et al (1982) record the relative bioavailability of oralketamine as being 17% and of intramuscular ketamine as being 93%. Sincethat article, several other studies have recorded the relative oralbioavailability of ketamine as being between 17 and 24%. Malinovsky etal (1996) record the relative bioavailability of intranasal ketamine asbeing 50% and of rectal ketamine as being 30%. Yanagihara et al (2003)record the relative bioavailability of both rectal and sublingualketamine as being 30%, whereas they found nasal bioavailability to be45%.

Although esketamine has been available for more than 40 years, there isvery little published literature into its relative bioavailability bynon-intravenous routes. Peltoniemi et al (2012) record the oralbioavailability of esketamine as being 11%, whereas Fanta et al (2015)found it to be only 8% and suggest that the first-pass metabolism ofesketamine is more extensive than that found with ketamine.Unfortunately, although the protocol of a study into the relativebioavailability of intranasal and oral esketamine, NCT02343289, wasalready described in 2015, no results have been published. Daly et al(2017) record that 56 mg and 84 mg administered intranasally producesplasma esketamine levels that are in the pharmacokinetic range achievedby an intravenous administration of 0.2 mg/kg of esketamine, suggestingthat the relative bioavailability of intranasal esketamine might beconsiderably lower than that of ketamine.

The relative efficacy and safety of the two enantiomers of ketamine hasalso been a source of considerable debate in the literature. Ebert et al(1997) record that esketamine has a 5 times greater affinity for theNMDA receptor than (R)-ketamine. Oye et al (1992) record that esketaminewas 4 times as potent as (R)-ketamine in reducing pain perception and incausing auditory and visual disturbances. Domino (2010) records thatalthough esketamine appears more potent than (R)-ketamine, it alsopresents with greater undesirable psychotomimetic side effects. Incontrast, Zhang et al (2014) and Yang et al (2015) have recorded that(R)-ketamine showed greater potency and longer-lasting antidepressanteffects than esketamine in animal models of depression withoutpsychotomimetic side effects and abuse liability. This has led some,such as Hashimoto (2016), to suggest that the anti-depressive effect ofthese molecules might not be due to NMDA receptor antagonism.

Despite the more recent interest in the use of ketamine and itsenantiomers in the treatment of depression, most clinical reportsdescribe the effects after a single administration. Blonk et al (2010)provide an extensive review of the doses recorded for chronicadministration of oral ketamine in pain therapy and shows that typicallyhigh doses of 200 mg/d or more were prescribed for time periods of up toand greater than a year. Paslakis et al (2010) record four case reportsof administering up to 1.25 mg/kg/d of oral esketamine as concomitanttherapy in patients suffering from depression over a 14 day timeframewith two patients receiving up to 150 mg/d for 7 of their treatmentdays. Daly et al (2015) record the administration of 28 mg, 56 mg, and84 mg of esketamine intranasally to patients twice a week for up to 14days followed by an open label extension study of reduced dosingfrequency for an additional 9 weeks, with all patients starting thisextension on 56 mg/r^(d) week and most completing the study on 84mg/2^(rd) week.

U.S. patent application Ser. No. 16/592,930 details an efficaciousmethod of treating major depressive disorder (MDD) by administering anoral dosage form of between about 5 mg and about 40 mg of esketamineover a treatment regimen of at least 28 days. Said application explainsthat for chronic therapy with an oral dosage form of esketamine, inorder to preserve an, at least 10 fold, safety margin over the genotoxicfindings presented, a maximum safe dose of 40 mg is allowable.

Surprisingly, it has now been found that chronic oral administration ofdoses of esketamine greater than 40 mg are safe and efficacious, withoutany increased risk of genotoxicity or mutagenicity.

SUMMARY OF THE INVENTION

In one embodiment, the invention relates to a method of treating majordepressive disorder (MDD) in a human patient in need thereof comprisingorally administering to said patient an oral dosage form comprisingbetween about 41 mg and about 80 mg of esketamine over a treatmentregimen of at least 28 days.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to methods of treating majordepressive disorder in a human patient in need thereof comprising orallyadministering to said patient an oral dosage form comprising about 41 mgand about 80 mg (e.g., 41 mg to 80 mg) of esketamine over a treatmentregimen of at least 28 days.

As used herein, the term “major depressive disorder”, or MDD, ischaracterized as a psychiatric disorder meeting five criteria: 1) thepresence during the same 2 week period which together represent a changefrom previous functioning, of a depressed/sad mood or a loss of interestand pleasure, together with five (or more) of the following additionalcriteria occurring nearly every day i) depressed/sad mood ii) loss ofinterest and pleasure iii) significant weight loss when not dieting orweight gain or a decrease or increase in appetite iv) insomnia orhypersomnia v) psychomotor agitation or retardation vi) fatigue or lossof energy vii) feelings of worthlessness or excessive or inappropriateguilt viii) diminished ability to think or concentrate or indecisivenessix) recurrent thoughts of death or suicidal ideation, planning orattempt: 2) the symptoms cause clinically significant distress orimpairment in social, occupational or other functioning: 3) the episodeis not better accounted for by a psychotic disorder: 4) the episode isnot attributable to the physiological effects of a substance or toanother medical condition: 5) there has never been a manic or hypomanicepisode (Diagnostic and Statistical Manual of Mental Disorders, 5thEdition, American Psychiatric Association, 2013). Other indicationscontemplated include treating, preventing, or ameliorating one or moresymptoms of a disorder including, but not limited to, Rett syndrome,depression, refractory depression, suicidality, obsessive-compulsivedisorder, fibromyalgia, post-traumatic stress syndrome, autism spectrumdisorder, and depression associated with genetic disorders.

In one embodiment, the major depressive disorder is with anxiousdistress. In another embodiment, the disorder is with mixed features. Inanother embodiment, the disorder is with melancholic features. Inanother embodiment, the disorder is with atypical features. In anotherembodiment, the disorder is with mood-congruent psychotic features. Inanother embodiment, the disorder is with mood-incongruent psychoticfeatures. In another embodiment, the disorder is with catatonia. Inanother embodiment, the disorder is with peripartum onset. In anotherembodiment, the disorder is with seasonal pattern.

In one embodiment, the major depressive disorder has not responded toadequate doses and treatment duration of antidepressants other thanketamine or esketamine. In some aspects, the non-responder has failed todemonstrate an improvement of up to 25% in MADRS score, or a similarpsychometric score, after adequate doses and treatment duration ofantidepressants other than ketamine or esketamine. In other aspects, thenon-responder has demonstrated an incomplete improvement of between25-50% in MADRS score, or a similar psychometric score, after adequatedoses and treatment duration of antidepressants other than ketamine oresketamine. In other aspects, the non-responder has demonstrated aninadequate improvement of up to 50% in MADRS score, or a similarpsychometric score, after adequate doses and treatment duration ofantidepressants other than ketamine or esketamine. In some aspects, theadequate doses and treatment duration of antidepressants other thanketamine or esketamine, refers to doses and treatment duration of one,or more, antidepressants other than ketamine or esketamine during thecurrent depressive episode. In other aspects, the adequate course refersto the non-response to doses and treatment duration of one, or more,antidepressants other than ketamine or esketamine during a previousdepressive episode. In other aspects, the adequate course refers to thenon-response to doses and treatment duration of one, or more,antidepressants other than ketamine or esketamine both during a previousdepressive episode and during the current depressive episode. In someaspects, the disorder is treatment-refractory or treatment-resistantdepression, i.e., depression that has failed to respond to adequatedoses and treatment duration of at least two antidepressants other thanketamine or esketamine.

As used herein, the term “treating major depressive disorder” can referto a reduction of the symptoms of Major Depressive Disorder, as measuredby reduction in the Montgomery—Asberg Depression Rating Scale (MADRS)score. In some aspects, the term “treating major depressive disorder”refers to a change from baseline, as measured the MADRS score. In someaspects, the term “treating major depressive disorder” refers to aremission, as measured by reduction in the MADRS score. In some aspects,the term “treating major depressive disorder” refers to a 50% or greaterimprovement, as measured the MADRS score.

In other aspects, the term “treating major depressive disorder” refersto change from baseline on Sheehan Disability Scale (SDS).

In other aspects, the term “treating major depressive disorder” refersto change from baseline on self-rated Symptoms of DepressionQuestionnaire (SDQ).

In other aspects, the term “treating major depressive disorder” refersto change from baseline on the physician-administered Clinical GlobalImpression Improvement (CGI-I).

In other aspects, the term “treating major depressive disorder” refersto change from baseline on the physician-administered Global ImpressionSeverity (CGI-S).

In other aspects, the term “treating major depressive disorder” refersto change from baseline on Generalized Anxiety Disorder 7 items scale.

In one embodiment, said increases, decreases and reductions of scoresand/or presentations of symptoms can be assessed in comparison to thescores and/or presentations of symptoms as identified before treatmentis initiated, i.e., baseline. In another embodiment, said increases,decreases and reductions of scores and/or presentations of symptoms canbe assessed in comparison to the scores and/or presentations of symptomsas identified in a different treatment group. In one embodiment, thedifferent treatment group is a second medication other than ketamine oresketamine. In another embodiment, the different treatment group is aplacebo.

The methods of the disclosure will exhibit an acceptable safety and/ortolerability profile. That is, the benefits achieved using the methodsof the disclosure will outweigh any safety and/or tolerabilityconsiderations exhibited by using the disclosed methods, as compared toplacebo. In other aspects, the benefits achieved using the methods ofthe disclosure will outweigh any safety and/or tolerabilityconsiderations exhibited by using the disclosed methods, as compared toother methods of treating MDD, including treatment-resistant MDD. Othermethods of treating MDD, including treatment-resistant MDD include othermethods of using ketamine and esketamine. For example, the benefitsachieved using the methods of the disclosure will outweigh any adverseevents including, for example, untoward changes in hematology,biochemistry, urinalysis, immunological parameters, physical examinationfindings, blood pressure, and/or heart rate, as compared to placebo. Inother aspects, the benefits achieved using the methods of the disclosurewill outweigh any adverse events including, for example, changes inhematology, biochemistry, urinalysis, immunological parameters, physicalexamination findings, blood pressure, and/or heart rate, as compared toother methods of treating MDD, including treatment-resistant MDD.

In other aspects, the benefits achieved using the methods of thedisclosure with outweigh any adverse events in 12 lead ECG findings,method discontinuation, Digit Symbol Substitution Test (DSST), reactiontime test (Cambridge COGNITION and/or Cogstate battery), selfadministered Stanford sleepiness scale, a Bladder Pain/InterstitialCystitis Symptom Score (BPIC-SS), a Modified Observer'sAlertness/Sedation Scale (MOAA/S), a Clinician-Administered DissociativeStates Scale (CADSS), a Suicidality Scale-Clinician-Rated ColumbiaSuicide Severity Rating Scale (C-SSRS), 4 items positive symptomssubscale from the Brief Psychiatric Rating Scale (BPRS), and/or 20 itemPhysician Withdrawal Checklist (PWC-20), as compared to placebo. Inother aspects, the benefits achieved using the methods of the disclosurewith outweigh any adverse events in 12 lead ECG findings, methoddiscontinuation, Digit Symbol Substitution Test (DSST), reaction timetest (Cambridge COGNITION and/or Cogstate battery), self administeredStanford sleepiness scale, a Bladder Pain/Interstitial Cystitis SymptomScore (BPIC-SS), a Modified Observer's Alertness/Sedation Scale(MOAA/S), a Clinician-Administered Dissociative States Scale (CADSS), aSuicidality Scale-Clinician-Rated Columbia Suicide Severity Rating Scale(C-SSRS), 4 items positive symptoms subscale from the Brief PsychiatricRating Scale (BPRS), and/or 20 item Physician Withdrawal Checklist(PWC-20), as compared to other methods of treating MDD, includingtreatment-resistant MDD.

As used herein, the term “ketamine” shall refer to the chemical compounddl 2-(2-chlorophenyl)-2(methylamino) cyclohexanone, or apharmaceutically acceptable salt thereof.

As used herein, the term “esketamine” shall refer to the (S)-enantiomerof ketamine also known as the chemical compound(25)-2-(2-Chlorophenyl)-2-(methylamino) cyclohexanone, or apharmaceutically acceptable salt thereof. As used herein, the term“esketamine” shall be understood to be to the exclusion of the compoundas found, without an enantiomeric excess, in ketamine, or apharmaceutically acceptable salt thereof. In one embodiment, theesketamine, or a pharmaceutically acceptable salt thereof, is thehydrochloride salt of esketamine, i.e., esketamine hydrochloride.

As used herein, the term “(R)-ketamine” shall refer to the(R)-enantiomer of ketamine also known as the chemical compound(2R)-2-(2-Chlorophenyl)-2-(methylamino) cyclohexanone, or apharmaceutically acceptable salt thereof. As used herein, the term“(R)-ketamine” shall be understood to be to the exclusion of thecompound as found, without an enantiomeric excess, in ketamine, or apharmaceutically acceptable salt thereof.

As used herein, the term “(S)-norketamine” shall refer to the(S)-enantiomer of norketamine also known as the chemical compound(25)-2-(2-Chlorophenyl)-2-(amino) cyclohexanone, or a pharmaceuticallyacceptable salt thereof. As used herein, the term “(S)-norketamine”shall be understood to be to the exclusion of the compound as found,without an enantiomeric excess, in norketamine, or a pharmaceuticallyacceptable salt thereof.

As used herein, the term “(2S,6S)-OH-norketamine” shall refer to the(2S,6S)-enantiomer of hydroxynorketamine also known as the chemicalcompound (25,65)-2-Amino-2-(2-chlorophenyl)-6-hydroxycyclohexanone, or apharmaceutically acceptable salt thereof. As used herein, the term“(2S,6S)-OH-Norketamine” shall be understood to be to the exclusion ofthe compound as found, without an enantiomeric excess, inhydroxynorketamine, or a pharmaceutically acceptable salt thereof.

The chemical compounds described herein according to the invention arealso intended to include such compounds wherein the molecular structuresinclude isotopes of carbon, hydrogen and nitrogen atoms occurring onthose structures. Isotopes include those atoms having the same atomicnumber but different mass numbers. For example, isotopes of hydrogeninclude deuterium. Isotopes of carbon include ¹³C. Isotopes of nitrogeninclude ¹⁵N .

Accordingly, within the chemical structure of any chemical compoundtaught in this application as suitable for the formulations disclosedherein:

-   -   any hydrogen atom or group of hydrogen atoms, could suitably be        replaced by an isotope of hydrogen, i.e., deuterium;    -   any carbon atom or group of carbon atoms, could suitably be        replaced by an isotope of carbon, i.e., ¹³C; and    -   any nitrogen atom or group of nitrogen atoms, could suitably be        replaced by an isotope of nitrogen, i.e., ¹⁵N.

As used herein, the term “treatment regimen” shall refer to time periodduring which the human patient, in need thereof, will be treated by morethan one, either daily or intermittent, administrations of esketamine.In a preferred embodiment of the invention, the treatment regimen willextend for at least 28 days. In another preferred embodiment, thetreatment regimen will extend for at least 30 days. In another preferredembodiment, the treatment regimen will be for 28 days to about 365 days.In another preferred embodiment, the treatment regimen will be for 28days to about 730 days. Another preferred embodiment, the treatmentregimen will extend for at least one month. In another preferredembodiment, the treatment regimen will extend for at least 1 year (365days). In another preferred embodiment of the invention, the treatmentregimen will extend for at least about 730 days, that is, at least about2 years. In another embodiment, the treatment regimen varies over thecourse of the 28 to about 730 days (i.e., about two years). A medicalprofessional skilled in the art of psychiatry will be able to determinethe administration regimen over the 28 to about 730 days (e.g. about twoyears).

In one embodiment, the reduction of the symptoms of major depressivedisorder are on or after day 28 of the treatment regimen. In anotherembodiment, the reduction of the symptoms of major depressive disorderare on or after day 30 of the treatment regimen. In another embodiment,the reduction of the symptoms of major depressive disorder are on orafter day 365 of the treatment regimen. In another embodiment, thereduction of the symptoms of major depressive disorder are on or afterday 730 of the treatment regimen. In one embodiment, the treatmentregimen results in a reduction of the symptoms of major depressivedisorder after at least 7 days of treatment. In another embodiment, thetreatment regimen results in a reduction of the symptoms of majordepressive disorder after at least 14 days of treatment. In anotherembodiment, the treatment regimen results in a reduction of the symptomsof major depressive disorder after at least 21 days of treatment. Inanother embodiment, the treatment regimen results in a reduction of thesymptoms of major depressive disorder after at least 28 days oftreatment. In another embodiment, the treatment regimen results in areduction of the symptoms of major depressive disorder after at least365 days of treatment. In another embodiment, the treatment regimenresults in a reduction of the symptoms of major depressive disorderafter at least 730 days of treatment.

In one embodiment, the reduction of the symptoms of major depressivedisorder are on or after day 28 of the treatment regimen and are incomparison to the scores and/or presentations of symptoms as identifiedbefore treatment is initiated, i.e. baseline. In another embodiment,reduction of the symptoms of major depressive disorder are on or afterday 28 of the treatment regimen and are in comparison to the scoresand/or presentations of symptoms as identified in a different treatmentgroup. In one embodiment, the different treatment group is a secondmedication other than ketamine or esketamine. In another embodiment, thedifferent treatment group is a placebo.

It is understood that where a parameter range is provided, all integerswithin that range, and tenths thereof, are also provided by theinvention. For example, “1-30 ng/ml” includes 1.1 ng/ml, 1.2 ng/ml, 1.3ng/ml, etc. up to 30 ng/ml. In another example, “0.1-2.5 mg/day”includes 0.1 mg/day, 0.2 mg/day, 0.3 mg/day, etc. up to 2.5 mg/day.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by orallyadministering to said patient of an oral dosage form comprising about 41mg and about 80 mg, preferably 41 mg to 80 mg, of esketamine over atreatment regimen of at least 28 days.

In some aspects, oral dosage forms of the disclosure include esketamine,i.e., esketamine as a free base. In other aspects, oral dosage forms ofthe disclosure include pharmaceutically acceptable salts of esketamine.As used herein, amounts of esketamine present in the oral dosage formsof the disclosure refer to amounts of esketamine free base. For example,in those aspects wherein the oral dosage form comprises esketamine freebase, “60 mg of esketamine” refers to 60 mg of the esketamine free basein the oral dosage form. In aspects wherein the oral dosage formcomprises a pharmaceutically acceptable salt of esketamine, such asesketamine hydrochloride, “60 mg of esketamine” refers to 60 mgesketamine free base, based on 69.18 mg of esketamine hydrochloride inthe oral dosage form.

In one preferred embodiment of the invention, the oral administration tosaid patient is of an oral dosage form comprising about 45 mg ofesketamine, preferably 45 mg of esketamine. In another preferredembodiment of the invention, the oral administration to said patient isof an oral dosage form comprising about 50 mg of esketamine, preferably50 mg of esketamine. In another preferred embodiment, the oraladministration to said patient is of an oral dosage form comprisingabout 55 mg of esketamine, preferably 55 mg of esketamine. In anotherpreferred embodiment, the oral administration to said patient is of anoral dosage form comprising about 60 mg of esketamine, preferably 60 mgof esketamine. In another preferred embodiment, the oral administrationto said patient is of an oral dosage form comprising about 65 mg ofesketamine, preferably 65 mg of esketamine. In another preferredembodiment, the oral administration to said patient is of an oral dosageform comprising about 70 mg of esketamine, preferably 70 mg ofesketamine. In another preferred embodiment, the oral administration tosaid patient is of an oral dosage form comprising about 75 mg ofesketamine, preferably 75 mg of esketamine. In yet another preferredembodiment, the oral administration to said patient is of an oral dosageform comprising about 80 mg of esketamine, preferably 80 mg ofesketamine. In one embodiment of the invention, the oral administrationto said patient is of an oral dosage form comprising about 41 to about45 mg of esketamine, for example, 41 to 45 mg of esketamine. In anotherembodiment of the invention, the oral administration to said patient isof an oral dosage form comprising about 41 to about 50 mg of esketamine,for example, 41 to 50 mg of esketamine. In another embodiment of theinvention, the oral administration to said patient is of an oral dosageform comprising about 41 to about 55 mg of esketamine, for example, 41to 55 mg of esketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 41 to about 60 mg of esketamine, for example, 41 to 60 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 41 to about 65 mg of esketamine, for example, 41 to 65 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 41 to about 70 mg of esketamine, for example, 41 to 70 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 41 to about 75 mg of esketamine, for example, 41 to 75 mg ofesketamine. In yet another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 41 to about 80 mg of esketamine, for example, 41 to 80 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 45 to about 50 mg of esketamine, for example, 45 to 50 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 45 to about 55 mg of esketamine, for example, 45 to 55 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 45 to about 60 mg of esketamine, for example, 45 to 60 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 45 to about 65 mg of esketamine, for example, 45 to 65 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 45 to about 70 mg of esketamine, for example, 45 to 70 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 45 to about 75 mg of esketamine, for example, 45 to 75 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 45 to about 80 mg of esketamine, for example, 45 to 80 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 50 to about 55 mg of esketamine, for example, 50 to 55 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 50 to about 60 mg of esketamine, for example, 50 to 60 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 50 to about 65 mg of esketamine, for example, 50 to 65 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 50 to about 70 mg of esketamine, for example, 50 to 70 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 50 to about 75 mg of esketamine, for example, 50 to 75 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 50 to about 80 mg of esketamine, for example, 50 to 80 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 55 to about 60 mg of esketamine, for example, 55 to 60 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 55 to about 65 mg of esketamine, for example, 55 to 65 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 55 to about 70 mg of esketamine, for example, 55 to 70 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 55 to about 75 mg of esketamine, for example, 55 to 75 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 55 to about 80 mg of esketamine, for example, 55 to 80 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 60 to about 65 mg of esketamine, for example, 60 to 65 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 60 to about 70 mg of esketamine, for example, 60 to 70 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 60 to about 75 mg of esketamine, for example, 60 to 75 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 60 to about 80 mg of esketamine, for example, 60 to 80 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 65 to about 70 mg of esketamine, for example, 65 to 70 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 65 to about 75 mg of esketamine, for example, 65 to 75 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 65 to about 80 mg of esketamine, for example, 65 to 80 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 70 to about 75 mg of esketamine, for example, 70 to 75 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 70 to about 80 mg of esketamine, for example, 70 to 80 mg ofesketamine. In another embodiment of the invention, the oraladministration to said patient is of an oral dosage form comprisingabout 75 to about 80 mg of esketamine, for example, 75 to 80 mg ofesketamine.

Without wanting to be bound to any particular theory, it is believedthat a therapeutic effect of repeated oral dosing of esketamine in thetreatment of major depressive disorder can be achieved by eitheradministering higher doses of the drug at longer intervals oradministering lower doses of the drug at shorter intervals. As describedherein, the present invention allows for equivalent exposure over timeof the drug and its metabolites and lower peak concentrations, reducesthe overall risk of genotoxic events and improves the clinical safetyprofile.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of an oral dosage form comprising about41 mg and about 80 mg of esketamine, preferably 41 mg to 80 mg ofesketamine, wherein the esketamine Cmax of said administration is 30ng/ml or less.

As used herein, the term “C_(max)” shall refer to the mean (average)observed maximum plasma concentration assayed after any singleadministration. In some embodiments the method disclosed herein furthercomprises measuring plasma levels in the patient.

In one embodiment of the invention, the esketamine C. of saidadministration is 30 ng/ml or less, 29 ng/ml or less, 28 ng/ml or less,27 ng/ml or less, 26 ng/ml or less, 25 ng/ml or less, 24 ng/ml or less,23 ng/ml or less, 22 ng/ml or less, 21 ng/ml or less, 20 ng/ml or less,19 ng/ml or less, 18 ng/ml or less, 17 ng/ml or less, 16 ng/ml or less,15 ng/ml or less, 14 ng/ml or less, 13 ng/ml or less, 12 ng/ml or less,11 ng/ml or less, 10 ng/ml or less, 9 ng/ml or less, 8 ng/ml or less, 7ng/ml or less, 6 ng/ml or less, 5 ng/ml or less, 4 ng/ml or less, 3ng/ml or less, 2 ng/ml or less, or 1 ng/ml or less. In one preferredembodiment of the invention, the esketamine C. of said administration is30 ng/ml or less. In another preferred embodiment of the invention, theesketamine C. of said administration is 15 ng/ml or less. In onepreferred embodiment of the invention, the esketamine Cmax of saidadministration is between 15 ng/mL and 30 ng/mL. In one preferredembodiment of the invention, the esketamine C. of said administration isbetween 10 ng/mL and 15 ng/mL. In one preferred embodiment of theinvention, the esketamine C. of said administration is between 5 ng/mLand 15 ng/mL. In one preferred embodiment of the invention, theesketamine C. of said administration is between 11 ng/mL and 13 ng/mL.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of an oral dosage form comprising about41 mg and about 80 mg of esketamine, for example, 41 mg to 80 mg ofesketamine, wherein the esketamine AUCo of said administration is 60ng*h/ml or less.

As used herein, the term “AUC” shall refer to the area under the plasmaconcentration/time curve after any single administration. The term“AUC_(0-t)” shall refer to the area under the plasma concentration/timecurve from time 0 to the last quantifiable concentration after anysingle administration and the term “AUCO-_(inf)” shall refer to the areaunder the plasma concentration/time curve from time 0 until theextrapolated concentration at infinity after any single administration.The term “AUC_(tan)” shall refer to the area under the plasmaconcentration/time curve over the steady state dosing interval.

In one embodiment of the invention, the esketamine AUC_(0-t) of saidadministration is 60 ng*h/ml, 59 ng*h/ml, 58 ng*h/ml, 57 ng*h/ml, 56ng*h/ml, 55 ng*h/ml, 54 ng*h/ml, 53 ng*h/ml, 52 ng*h/ml, 51 ng*h/ml, 50ng*h/ml, 49 ng*h/ml, 48 ng*h/ml, 47 ng*h/ml, 46 ng*h/ml, 45 ng*h/ml, 44ng*h/ml, 43 ng*h/ml, 42 ng*h/ml, 41 ng*h/ml, 40 ng*h/ml, 39 ng*h/ml, 38ng*h/ml, 37 ng*h/ml, 36 ng*h/ml, 35 ng*h/ml, 34 ng*h/ml, 33 ng*h/ml, 32ng*h/ml, 31 ng*h/ml, 30 ng*h/ml, 29 ng*h/ml, 28 ng*h/ml, 27 ng*h/ml, 26ng*h/ml, 25 ng*h/ml, 24 ng*h/ml, 23 ng*h/ml, 22 ng*h/ml, 21 ng*h/ml, 20ng*h/ml, 19 ng*h/ml, 18 ng*h/ml, 17 ng*h/ml, 16 ng*h/ml, 15 ng*h/ml, 14ng*h/ml, 13 ng*h/ml, 12 ng*h/ml, 11 ng*h/ml, 10 ng*h/ml, 9 ng*h/ml, 8ng*h/ml, 7 ng*h/ml, 6 ng*h/ml, 5 ng*h/ml, 4 ng*h/ml, 3 ng*h/ml, 2ng*h/ml, or 1 ng*h/ml. In one preferred embodiment of the invention, theesketamine AUC_(0-t) of said administration is 60 ng*h/ml or less. Inanother preferred embodiment of the invention, the esketamine AUC_(0-t)of said administration is 30 ng*h/ml or less. In one preferredembodiment of the invention, the esketamine AUC_(0-t) of saidadministration is between 30 ng*h/ml and 60 ng*h/ml. In one preferredembodiment of the invention, the esketamine AUC_(0-t) of saidadministration is between 15 ng*h/ml and 30 ng*h/ml.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of a dosage form, wherein said dosageform provides for an (S)-norketamine C_(max) of 150 ng/ml or less.

In one embodiment of the invention, the (S)-norketamine C_(max) of saidadministration is 150 ng/ml or less, 145 ng/ml or less, 140 ng/ml orless, 139 ng/ml or less, 138 ng/ml or less, 137 ng/ml or less, 136 ng/mlor less, 135 ng/ml or less, 134 ng/ml or less, 133 ng/ml or less, 132ng/ml or less, 131 ng/ml or less, 130 ng/ml or less, 129 ng/ml or less,128 ng/ml or less, 127 ng/ml or less, 126 ng/ml or less, 125 ng/ml orless, 120 ng/ml or less, 115 ng/ml or less, 110 ng/ml or less, 105 ng/mlor less, 100 ng/ml or less, 95 ng/ml or less, 90 ng/ml or less, 85 ng/mlor less, 80 ng/ml or less, 75 ng/ml or less, 74 ng/ml or less, 73 ng/mlor less, 72 ng/ml or less, 71 ng/ml or less, 70 ng/ml or less, 69 ng/mlor less, 68 ng/ml or less, 67 ng/ml or less, 66 ng/ml or less, 65 ng/mlor less, 64 ng/ml or less, 63 ng/ml or less, 62 ng/ml or less, 61 ng/mlor less, 60 ng/ml or less, 55 ng/ml or less, 50 ng/ml or less, 45 ng/mlor less, 40 ng/ml or less, 35 ng/ml or less, 34 ng/ml or less, 33 ng/mlor less, 32 ng/ml or less, 31 ng/ml or less, 30 ng/ml or less, 25 ng/mlor less, 20 ng/ml or less, 19 ng/ml or less, 18 ng/ml or less, 17 ng/mlor less, 16 ng/ml or less or 15 ng/ml or less. In one preferredembodiment of the invention, the (S)-norketamine C. of saidadministration is 150 ng/ml or less. In another preferred embodiment ofthe invention, the (S)-norketamine C_(max) of said administration is 75ng/ml or less. In another preferred embodiment of the invention, the(S)-norketamine C_(max) of said administration is 35 ng/ml or less. Inanother preferred embodiment of the invention, the (S)-norketamineC_(max) of said administration is 20 ng/ml or less. In one preferredembodiment of the invention, the (S)-norketamine C. of saidadministration is between 15 ng/mL and 150 ng/mL. In another preferredembodiment of the invention, the (S)-norketamine C. of saidadministration is between 15 ng/mL and 20 ng/mL. In another preferredembodiment of the invention, the (S)-norketamine C_(max) of saidadministration is between 30 ng/mL and 35 ng/mL. In another preferredembodiment of the invention, the (S)-norketamine C_(max) of saidadministration is between 60 ng/mL and 75 ng/mL. In another preferredembodiment of the invention, the (S)-norketamine C. of saidadministration is between 125 ng/mL and 140 ng/mL. In another preferredembodiment of the invention, the (S)-norketamine C. of saidadministration is between 60 ng/mL and 140 ng/mL.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of a dosage form, wherein said dosageform provides for an (S)-norketamine AUC_(0-t) of 850 ng*h/ml or less.

In one embodiment of the invention, the (S)-norketamine AUC_(0-t) ofsaid administration is 850 ng*h/ml or less, 845 ng*h/ml or less, 840ng*h/ml or less, 839 ng*h/ml or less, 838 ng*h/ml or less, 837 ng*h/mlor less, 836 ng*h/ml or less, 835 ng*h/ml or less, 834 ng*h/ml or less,832 ng*h/ml or less, 831 ng*h/ml or less, 830 ng*h/ml or less, 829ng*h/ml or less, 828 ng*h/ml or less, 827 ng*h/ml or less, 826 ng*h/mlor less, 825 ng*h/ml or less, 824 ng*h/ml or less, 823 ng*h/ml or less,822 ng*h/ml or less, 821 ng*h/ml or less, 820 ng*h/ml or less, 815ng*h/ml or less, 810 ng*h/ml or less, 805 ng*h/ml or less, 800 ng*h/mlor less, 795 ng*h/ml or less, 790 ng*h/ml or less, 785 ng*h/ml or less,780 ng*h/ml or less, 775 ng*h/ml or less, 770 ng*h/ml or less, 765ng*h/ml or less, 760 ng*h/ml or less, 755 ng*h/ml or less, 750 ng*h/mlor less, 745 ng*h/ml or less, 740 ng*h/ml or less, 735 ng*h/ml or less,730 ng*h/ml or less, 725 ng*h/ml or less, 720 ng*h/ml or less, 710ng*h/ml or less, 700 ng*h/ml or less, 690 ng*h/ml or less, 680 ng*h/mlor less, 670 ng*h/ml or less, 660 ng*h/ml or less, 650 ng*h/ml or less,640 ng*h/ml or less, 630 ng*h/ml or less, 620 ng*h/ml or less, 610ng*h/ml or less, 600 ng*h/ml or less, 590 ng*h/ml or less, 580 ng*h/mlor less, 570 ng*h/ml or less, 560 ng*h/ml or less, 550 ng*h/ml or less,540 ng*h/ml or less, 530 ng*h/ml or less, 520 ng*h/ml or less, 510ng*h/ml or less, 500 ng*h/ml or less, 490 ng*h/ml or less, 480 ng*h/mlor less, 470 ng*h/ml or less, 460 ng*h/ml or less, 450 ng*h/ml or less,440 ng*h/ml or less, 430 ng*h/ml or less, 425 ng*h/ml or less, 420ng*h/ml or less, 419 ng*h/ml or less, 418 ng*h/ml or less, 417 ng*h/mlor less, 416 ng*h/ml or less, 415 ng*h/ml or less, 414 ng*h/ml or less,413 ng*h/ml or less, 412 ng*h/ml or less, 411 ng*h/ml or less, 410ng*h/ml or less, 405 ng*h/ml or less, 400 ng*h/ml or less, 390 ng*h/mlor less, 380 ng*h/ml or less, 380 ng*h/ml or less, 370 ng*h/ml or less,360 ng*h/ml or less, 350 ng*h/ml or less, 340 ng*h/ml or less, 330ng*h/ml or less, 320 ng*h/ml or less, 310 ng*h/ml or less, 300 ng*h/mlor less, 290 ng*h/ml or less, 280 ng*h/ml or less, 270 ng*h/ml or less,260 ng*h/ml or less, 250 ng*h/ml or less, 240 ng*h/ml or less, 230ng*h/ml or less, 220 ng*h/ml or less, 215 ng*h/ml or less, 210 ng*h/mlor less, 209 ng*h/ml or less, 208 ng*h/ml or less, 207 ng*h/ml or less,206 ng*h/ml or less, 205 ng*h/ml or less, 200 ng*h/ml or less, 190ng*h/ml or less, 180 ng*h/ml or less, 170 ng*h/ml or less, 160 ng*h/mlor less, 150 ng*h/ml or less, 140 ng*h/ml or less, 130 ng*h/ml or less,120 ng*h/ml or less, 110 ng*h/ml or less, 105 ng*h/ml or less, 104ng*h/ml or less, 103 ng*h/ml or less or 102 ng*h/ml or less. In onepreferred embodiment of the invention, the (S)-norketamine AUC_(0-t) ofsaid administration is 850 ng*h/ml or less. In another preferredembodiment of the invention, the (S)-norketamine AUC_(0-t) of saidadministration is 420 ng*h/ml or less. In another preferred embodimentof the invention, the (S)-norketamine AUC_(0-t) of said administrationis 210 ng*h/ml or less. In another preferred embodiment of theinvention, the (S)-norketamine AUC_(0-t) of said administration is 105ng*h/ml or less. In one preferred embodiment of the invention, the(S)-norketamine AUC_(0-t) of said administration is between 105 ng*h/mland 850 ng*h/ml. In another preferred embodiment of the invention, the(S)-norketamine AUC_(0-t) of said administration is between 105 ng*h/mland 850 ng*h/ml. In another preferred embodiment of the invention, the(S)-norketamine AUC_(0-t) of said administration is between 102 ng*h/mland 105 ng*h/ml. In another preferred embodiment of the invention, the(S)-norketamine AUC_(0-t) of said administration is between 205 ng*h/mland 210 ng*h/ml. In another preferred embodiment of the invention, the(S)-norketamine AUC_(0-t) of said administration is between 410 ng*h/mland 420 ng*h/ml. In another preferred embodiment of the invention, the(S)-norketamine AUC_(0-t) of said administration is between 820 ng*h/mland 840 ng*h/ml.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of a dosage form, wherein said dosageform provides for an (2S,6S)-OH-norketamine C. of 75 ng/ml or less.

In one embodiment of the invention, the (2S,6S)-OH-norketamine C. ofsaid administration is 75 ng/ml or less, 74 ng/ml or less, 73 ng/ml orless, 72 ng/ml or less, 71 ng/ml or less, 70 ng/ml or less, 69 ng/ml orless, 68 ng/ml or less, 67 ng/ml or less, 66 ng/ml or less, 65 ng/ml orless, 64 ng/ml or less, 63 ng/ml or less, 62 ng/ml or less, 61 ng/ml orless, 60 ng/ml or less, 55 ng/ml or less, 50 ng/ml or less, 45 ng/ml orless, 40 ng/ml or less, 35 ng/ml or less, 34 ng/ml or less, 33 ng/ml orless, 32 ng/ml or less, 31 ng/ml or less, 30 ng/ml or less, 25 ng/ml orless, 20 ng/ml or less, 19 ng/ml or less, 18 ng/ml or less, 17 ng/ml orless, 16 ng/ml or less or 15 ng/ml or less. In one preferred embodimentof the invention, the (2S,6S)-OH-norketamine C_(max) of saidadministration is 75 ng/ml or less. In another preferred embodiment ofthe invention, the (2S,6S)-OH-norketamine C_(max) of said administrationis 35 ng/ml or less. In another preferred embodiment of the invention,the (2S,6S)-OH-norketamine C_(max) of said administration is 20 ng/ml orless. In one preferred embodiment of the invention, the(2S,6S)-OH-norketamine C. of said administration is between 15 ng/mL and75 ng/mL. In another preferred embodiment of the invention, the(2S,6S)-OH-norketamine C. of said administration is between 15 ng/mL and20 ng/mL. In another preferred embodiment of the invention, the(2S,6S)-OH-norketamine C. of said administration is between 30 ng/mL and35 ng/mL. In another preferred embodiment of the invention, the(2S,6S)-OH-norketamine C. of said administration is between 60 ng/mL and75 ng/mL.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of a dosage form, wherein said dosageform provides for an (2S,6S)-OH-norketamine AUC_(0-t) of 850 ng*h/ml orless.

In one embodiment of the invention, the (2S,6S)-OH-norketamine AUC_(0-t)of said administration is 850 ng*h/ml or less, 845 ng*h/ml or less, 840ng*h/ml or less, 839 ng*h/ml or less, 838 ng*h/ml or less, 837 ng*h/mlor less, 836 ng*h/ml or less, 835 ng*h/ml or less, 834 ng*h/ml or less,832 ng*h/ml or less, 831 ng*h/ml or less, 830 ng*h/ml or less, 829ng*h/ml or less, 828 ng*h/ml or less, 827 ng*h/ml or less, 826 ng*h/mlor less, 825 ng*h/ml or less, 824 ng*h/ml or less, 823 ng*h/ml or less,822 ng*h/ml or less, 821 ng*h/ml or less, 820 ng*h/ml or less, 815ng*h/ml or less, 810 ng*h/ml or less, 805 ng*h/ml or less, 800 ng*h/mlor less, 795 ng*h/ml or less, 790 ng*h/ml or less, 785 ng*h/ml or less,780 ng*h/ml or less, 775 ng*h/ml or less, 770 ng*h/ml or less, 765ng*h/ml or less, 760 ng*h/ml or less, 755 ng*h/ml or less, 750 ng*h/mlor less, 745 ng*h/ml or less, 740 ng*h/ml or less, 735 ng*h/ml or less,730 ng*h/ml or less, 725 ng*h/ml or less, 720 ng*h/ml or less, 710ng*h/ml or less, 700 ng*h/ml or less, 690 ng*h/ml or less, 680 ng*h/mlor less, 670 ng*h/ml or less, 660 ng*h/ml or less, 650 ng*h/ml or less,640 ng*h/ml or less, 630 ng*h/ml or less, 620 ng*h/ml or less, 610ng*h/ml or less, 600 ng*h/ml or less, 590 ng*h/ml or less, 580 ng*h/mlor less, 570 ng*h/ml or less, 560 ng*h/ml or less, 550 ng*h/ml or less,540 ng*h/ml or less, 530 ng*h/ml or less, 520 ng*h/ml or less, 510ng*h/ml or less, 500 ng*h/ml or less, 490 ng*h/ml or less, 480 ng*h/mlor less, 470 ng*h/ml or less, 460 ng*h/ml or less, 450 ng*h/ml or less,440 ng*h/ml or less, 430 ng*h/ml or less, 425 ng*h/ml or less, 420ng*h/ml or less, 419 ng*h/ml or less, 418 ng*h/ml or less, 417 ng*h/mlor less, 416 ng*h/ml or less, 415 ng*h/ml or less, 414 ng*h/ml or less,413 ng*h/ml or less, 412 ng*h/ml or less, 411 ng*h/ml or less, 410ng*h/ml or less, 405 ng*h/ml or less, 400 ng*h/ml or less, 390 ng*h/mlor less, 380 ng*h/ml or less, 380 ng*h/ml or less, 370 ng*h/ml or less,360 ng*h/ml or less, 350 ng*h/ml or less, 340 ng*h/ml or less, 330ng*h/ml or less, 320 ng*h/ml or less, 310 ng*h/ml or less, 300 ng*h/mlor less, 290 ng*h/ml or less, 280 ng*h/ml or less, 270 ng*h/ml or less,260 ng*h/ml or less, 250 ng*h/ml or less, 240 ng*h/ml or less, 230ng*h/ml or less, 220 ng*h/ml or less, 215 ng*h/ml or less, 210 ng*h/mlor less, 209 ng*h/ml or less, 208 ng*h/ml or less, 207 ng*h/ml or less,206 ng*h/ml or less, 205 ng*h/ml or less, 200 ng*h/ml or less, 190ng*h/ml or less, 180 ng*h/ml or less, 170 ng*h/ml or less, 160 ng*h/mlor less, 150 ng*h/ml or less, 140 ng*h/ml or less, 130 ng*h/ml or less,120 ng*h/ml or less, 110 ng*h/ml or less, 105 ng*h/ml or less, 104ng*h/ml or less, 103 ng*h/ml or less or 102 ng*h/ml or less. In onepreferred embodiment of the invention, the (2S,6S)-OH-norketamineAUC_(0-t) of said administration is 850 ng*h/ml or less. In anotherpreferred embodiment of the invention, the (2S,6S)-OH-norketamineAUC_(0-t) of said administration is 420 ng*h/ml or less. In anotherpreferred embodiment of the invention, the (2S,6S)-OH-norketamineAUC_(0-t) of said administration is 210 ng*h/ml or less. In anotherpreferred embodiment of the invention, the (2S,6S)-OH-norketamineAUC_(0-t) of said administration is 105 ng*h/ml or less. In onepreferred embodiment of the invention, the (2S,6S)-OH-norketamineAUC_(0-t) of said administration is between 105 ng*h/ml and 850 ng*h/ml.In another preferred embodiment of the invention, the(2S,6S)-OH-norketamine AUC_(0-t) of said administration is between 105ng*h/ml and 850 ng*h/ml. In another preferred embodiment of theinvention, the (2S,6S)-OH-norketamine AUC_(0-t) of said administrationis between 102 ng*h/ml and 105 ng*h/ml. In another preferred embodimentof the invention, the (2S,6S)-OH-norketamine AUC_(0-t) of saidadministration is between 205 ng*h/ml and 210 ng*h/ml. In anotherpreferred embodiment of the invention, the (2S,6S)-OH-norketamineAUC_(0-t) of said administration is between 410 ng*h/ml and 420 ng*h/ml.In another preferred embodiment of the invention, the(2S,6S)-OH-norketamine AUC_(0-t) of said administration is between 820ng*h/ml and 840 ng*h/ml.

The present invention is further directed to a method of treating majordepressive disorder, in a human patient in need thereof by the oraladministration to said patient of an oral dosage form comprising betweenabout 41 mg and about 80 mg of esketamine, for example, 41 mg to 80 mg,of esketamine, wherein the administration is daily.

In one embodiment of the invention, the daily administration ofesketamine is provided in a single daily dose. In another embodiment ofthe invention, the daily administration of esketamine is provided in twodoses, in three doses, or in four doses, each dose being spread aboutequally over the 24 hour period.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of an oral dosage form comprising about41 mg to about 80 mg of esketamine, preferably 41 mg to 80 mg ofesketamine, wherein the administration is intermittent over thetreatment regimen.

In a preferred embodiment of the invention, the intermittentadministration is once every second day to about once a month or onceevery 4 weeks. In one embodiment of the invention, the intermittentadministration is once every second day, once every third day, twice aweek, once every fourth day, once every fifth day, once every sixth day,once a week, once every eighth day, once every ninth day, once everytenth day, once every eleventh day, once every twelfth day, once everythirteenth day, once every two weeks, once every three weeks or once amonth. In one preferred embodiment of the invention, the intermittentadministration is twice a week. In another preferred embodiment of theinvention, the intermittent administration is once a week. In yetanother preferred embodiment of the invention, the intermittentadministration is once a month. In yet another preferred embodiment ofthe invention, the intermittent administration is once every 4 weeks.

In one embodiment of the invention, frequency of the intermittentadministration can vary over the time period of the treatment regimen.In a preferred embodiment of the invention, the frequency of theintermittent administration is gradually reduced over the time period ofthe treatment regimen. In a more preferred embodiment of the invention,the frequency of the intermittent administration is reduced from twice aweek to once a week. In another preferred embodiment of the invention,the frequency of the intermittent administration is reduced from once aweek to once every two weeks. In an even more preferred embodiment ofthe invention, the frequency of the intermittent administration isreduced from twice a week to once a week to once every two weeks. Inanother preferred embodiment of the invention, the frequency of theintermittent administration is maintained consistently over the timeperiod of the treatment regimen.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of an oral dosage form comprising betweenabout 41 mg and about 80 mg of esketamine, preferably 41 mg to 80 mg ofesketamine, over a treatment regimen of at least 28 days wherein theadministration is self-administered. As used herein “self-administered”refers to administration wherein the patient is responsible for takingthe medication and is not assisted during the oral administration of theoral dosage form by a healthcare professional. In some aspects, one ormore of the administrations may be assisted by a healthcare professionaland one or more of the administration may be self-administered over thetreatment regimen. In one embodiment, said self-administration is in thepatient's own home. In a preferred embodiment, said self-administrationis at night. In a more preferred embodiment, said self-administration isbefore the patient goes to sleep.

In another embodiment, the patient has no restrictions on driving in the24 hours immediately following the oral administration of the oraldosage form comprising about between about 41 mg to about 80 mg ofesketamine, preferably 41 mg to 80 mg of esketamine. That is, the oraladministration of the oral dosage form does not result in a mental ormotor impairment that negatively affects the patient's ability tooperative a motor vehicle. In the 24 hours immediately following theadministration.

In yet another embodiment, the patient is restricted from driving for nomore than 10 hours after the oral administration of the oral dosage formcomprising about 41 mg to about 80 mg of esketamine, preferably 41 mg to80 mg of esketamine. In a preferred embodiment, the patient isrestricted from driving for no more than 8 hours after theadministration. In another preferred embodiment, the patient isrestricted from driving for no more than 6 hours after theadministration. In a more preferred embodiment, the patient isrestricted from driving for no more than 2 hours after theadministration. In a most preferred embodiment, the patient isrestricted from driving for no more than an hour after the oraladministration of the oral dosage form comprising about 41 mg to about80 mg of esketamine, preferably 41 mg to 80 mg of esketamine.

In one embodiment of the invention, the oral dosage form is a liquidpreparation such as a suspension, elixir, or solution. In anotherembodiment of the invention, the oral dosage forms are solidpreparations, for example, powders, capsules, caplets, gelcaps, andtablets. In a preferred embodiment, the oral dosage form is a tablet,gelcap, or capsule. In a more preferred embodiment, the oral dosage formis a tablet.

To prepare the preparations, i.e., the oral dosage forms, of thisinvention, esketamine, and optionally, at least one second medicationother than (R)-ketamine, are admixed with pharmaceutical carriersaccording to conventional pharmaceutical compounding techniques, whichcarriers may take a wide variety of forms depending of the form ofpreparation desired for administration. In preparing the oralpreparations, any of the usual pharmaceutical media may be employed.Thus, for liquid oral preparations, such as for example, suspensions,elixirs and solutions, suitable carriers and additives include water,glycols, oils, alcohols, flavoring agents, preservatives, coloringagents and the like. For solid oral preparations such as, for example,powders, capsules, caplets, gelcaps and tablets, suitable carriers andadditives include starches, sugars, diluents, granulating agents,lubricants, binders, disintegrating agents and the like. Because oftheir ease in administration, tablets and capsules represent the mostadvantageous oral dosage unit form, in which case solid pharmaceuticalcarriers are employed.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof by theadministration to said patient of an oral dosage form comprising about41 mg to about 80 mg of esketamine, preferably 41 mg to 80 mg ofesketamine, wherein the oral dosage form is an abuse deterrentformulation. In a more preferred embodiment, the abuse deterrentformulation is a tablet. Abuse deterrent tablet formulations can beprepared by methods known in the art including as found in U.S. Pat. No.7,955,619, WO2014006004, WO2008033523, WO2008023261, WO2016094358,WO2020225773 and US2004052731 each of which is hereby incorporated byreference.

The present invention is further directed to methods of treating majordepressive disorder in a human patient in need thereof by the oraladministration to said patient of an oral dosage form comprising about41 mg to about 80 mg of esketamine, preferably 41 mg to 80 mg ofesketamine, further comprising the administration of a second medicationother than (R)-ketamine.

In a preferred embodiment, the second medication is an antidepressant,an antimanic agent or an anxiolytic drug. In one embodiment of theinvention, the antidepressant is selected from the group consisting ofmono-amine oxidase inhibitors (MAOI), tricyclic antidepressants (TCA),serotonin specific reuptake inhibitors (SSRI), serotonin noradrenergicreuptake inhibitors (SNRI), noradrenaline reuptake inhibitor (NRI),“natural products” (such as Kava-Kava, St. John's Wort), dietarysupplement (such as s-adenosylmethionine) and others. More specifically,antidepressants include, but are not limited to, imipramine,amitriptyline, desipramine, nortriptyline, doxepin, protriptyline,trimipramine, maprotiline, amoxapine, trazodone, bupropion,chlomipramine, fluoxetine, citalopram, escitalopram, sertraline,paroxetine, tianeptine, agomelatine, nefazadone, venlafaxine,desvenlafaxine, vilazodone, vortioxetine, duloxetine, reboxetine,mirtazapine, mianserin, phenelzine, tranylcypromine, and/or moclobemide.

In another preferred embodiment, the second medication is an antimanicagent. In one embodiment of the invention, the antimanic agent isselected from the group consisting of carbamazepine, gabapentin, Lithiumor a pharmaceutically acceptable salt thereof, valproic acid andantipsychotic medications such as lurasidone, cariprazine, olanzapine,risperidone, quetiapine, paliperidone, aripiprazole and brexpiprazole.

In another preferred embodiment, the second medication is an anxiolyticdrug. In one embodiment of the invention, the anxiolytic drug isselected from the group consisting of Alprazolam, Bromazepam,Chlordiazepoxide, Clonazepam, Clorazepate, Diazepam, Flurazepam, Lorazepam, Oxazepam, Temazepam, Triazolam, Buspirone, Gepirone, Ispapirone,Hydroxyzine, Amobarbital, Pentobarbital, Phenobarbital, Thiopental andPropanolol.

The present invention is further directed to a method of treating majordepressive disorder in a human patient in need thereof, by the oraladministration to said patient of an oral dosage form comprising about41 mg to about 80 mg of esketamine, preferably 41 mg to 80 mg ofesketamine and an antidepressant selected from the group consisting offluoxetine, sertraline, paroxetine, citalopram, escitalopram,venlafaxine, desvenlafaxine, duloxetine, and fluvoxamine and wherein theadministration is daily over a treatment regimen of at least 28 days.

This invention will be better understood by reference to the Examples,which follow, but those skilled in the art will readily appreciate thatthe specific experiments detailed are only illustrative of the inventionas described more fully in the claims which follow thereafter.

EXAMPLES Example 1 In vitro Chromosomal Aberration Assay Example 1a:Esketamine

The clastogenic potential of esketamine was evaluated in the in vitromammalian chromosome aberration test using human peripheral bloodlymphocytes (HPBL) in both the absence and presence of an inducedmetabolic activation system (the 9000 g supernatant [S9] microsomalfraction of liver homogenate from rats exposed to Aroclor-1254).Clastogenicity was evaluated by microscopic examination of HPBL inmetaphase to determine the mitotic index (MI) and percentage ofmetaphase cells with numerical and/or structural chromosome aberrations.

The study was conducted in 2 phases, with a preliminary toxicity testused to determine the appropriate concentrations for the definitivechromosomal aberration assay. Water was used as a negative (vehicle)control. Toxicity (defined as ≥45% reduction in MI relative to thevehicle control) was evaluated at 9 concentrations, ranging from 0.0238to 238 μg/ml, after exposure of HPBL to esketamine for 20 hours in theabsence of S9 activation, or for 4 hours, either in the presence orabsence of S9 activation, followed by a 16-hour recovery period.Toxicity was not observed at any dose in any of the three treatmentconditions. Based upon these results, the doses chosen for thechromosomal aberration assay ranged from 30 to 238 μg/ml for all threetreatment conditions. All concentrations were between 98% to 101% of thenominal concentrations.

The definitive chromosome aberration assay evaluated HPBL cells afterexposure to esketamine for 20 hours in the absence of S9 activation, orfor 4 hours, either in the presence of absence of S9 activation,followed by a 16-hour recovery. Positive controls for chromosomalaberrations in non-activated and S9-activated evaluations, respectively,consisted of mitomycin C (MMC, 0.6 and 0.3 μg/mL for the 4- and 20-hourexposures, respectively) and cyclophosphamide (CP, 2.5, 5, and 7.5μg/mL). Water was associated with mean MI values from 13.4% to 16.5% andnumerical or structural chromosomal aberrations in 0% to 0.7% of thecells. In non-activated systems, MMC was associated with a mean MI valueof 9% with structural chromosomal aberrations in 13.3% of the cells. Inthe S9-activated system, CP was associated with a mean MI value of 6.2%and with structural aberrations in 10.7% of the cells. The results fornegative controls were within the range of historical controls and theresults for positive controls were statistically significant (p<0.01,Fisher's exact test). Thus the requirements for a valid test werefulfilled. In the chromosomal aberration assay, cytotoxicity (>45%reduction in mitotic index relative to the vehicle control) was notobserved at any esketamine dose in the non-activated 4- and 20-hourtreatment conditions. Cytotoxicity was observed at doses >200 μg/mL inthe S9-activated 4-hour exposure group. Initially, the doses selectedfor evaluation of chromosomal aberrations were 60, 120, and 238 μg/mLfor the non-activated 4- and 20-hour treatment conditions; and 30, 60,and 200 μg/mL for the S9-activated 4-hour treatment condition.

In the non-activated 4 and 20-hour exposure groups, no significant ordose-dependent increases in structural or numerical (polyploid orendoreduplicated cells) aberrations were observed at any dose (p >0.05;Fisher's Exact and Cochran-Armitage tests).

In the S9-activated 4-hour exposure group, a statistically significantincrease (5.0%) in structural aberrations was observed at 200 μg/mL (p<0.01; Fisher's Exact test). In order to confirm that the statisticalsignificance observed at the high dose was not due to cytotoxicity, alower dose (120 μg/mL) was included in the evaluation. A statisticallysignificant increase (4.3%) in structural aberrations was observed at120 μg/mL (p <0.01; Fisher's Exact test). The Cochran-Armitage test waspositive for a dose response (p <0.01). No significant or dose-dependentincreases in numerical (polyploid or endoreduplicated cells) aberrationswere observed at any dose (p>0.05; Fisher's Exact and Cochran-Armitagetests).

The results of the study indicate that esketamine was positive for theinduction of structural chromosomal aberrations and negative for theinduction of numerical chromosomal aberrations in the presence of theexogenous metabolic activation system. Esketamine was negative for theinduction of structural and numerical chromosomal aberrations in theabsence of the exogenous metabolic activation system.

Example 1b (S)-Norketamine

The clastogenic potential of (S)-norketamine was evaluated in the invitro mammalian chromosome aberration test using human peripheral bloodlymphocytes (HPBL) in both the absence and presence of an inducedmetabolic activation system (the 9000 g supernatant [S9] microsomalfraction of liver homogenate from rats exposed tophenobarbital/5,6-benzoflavone). Clastogenicity was evaluated bymicroscopic examination of HPBL in metaphase to determine the percentageof metaphase cells with numerical and/or structural chromosomeaberrations.

The study was conducted in 2 phases, with a preliminary toxicity testused to determine the appropriate concentrations for the definitivechromosomal aberration assay. Water was used as a negative (vehicle)control. In both phases, the cells were treated for 3 and 21 hours inthe absence of S9 mix and for 3 hours in the presence of S9 mix. Themitotic index was assessed for all cultures to determine cytotoxicity.Ten concentrations, ranging from 2.62 to 260.16 μg/mL, were evaluated inthe preliminary toxicity test. Toxicity was not observed at any dose inany of the three treatment conditions. Based on these results, thehighest concentration for the definitive chromosomal aberration assaywas based on the limit concentration (260.16 μg/mL, 1 mM) for this testsystem, where relatively no cytotoxicity was observed. (S)-Norketamineconcentrations of 93.66, 156.10 or 260.16 μg/mL were selected formetaphase analysis.

(S)-Norketamine caused no statistically significant increases in theproportion of metaphase figures containing chromosomal aberrations, atany analyzed concentration, when compared with the vehicle control. Allmean values for the vehicle control (water), and all (S)-norketaminetreatment concentrations were below to the laboratory historical controlrange, when taken at the upper 95% control limit.

No statistically significant increases in the proportion of polyploid orendoreduplicated metaphase cells were observed during metaphaseanalysis, under any treatment condition, when compared with the vehiclecontrol whereas both positive control compounds, mytomycin C andcyclophosphamide, caused statistically significant increases in theproportion of aberrant cells, demonstrating the sensitivity of the testsystem and the efficacy of the S9 mix.

In conclusion, the results of the in vitro mammalian chromosomeaberration test using human peripheral blood lymphocytes indicate that(S)-norketamine has shown no evidence of causing an increase in thefrequency of structural chromosome aberrations with or without S9.Therefore, under the conditions of this experiment, (S)-norketamine wasnon-clastogenic, or negative for the induction of structural andnumerical chromosomal aberrations.

Example 2 In vivo Single Cell Gel Electrophoresis Assay and MammalianErythrocyte Micronucleus Test of Esketamine in Sprague Dawley Rats

The potential of esketamine to induce DNA strand breaks in the liver andalso assess the potential induction of micronuclei in the bone marrowcells of Crl:CD(SD) rats. Animals were treated with esketamine orally onthree occasions, the second dose being administered approximately 24hours after the first dose, with the third dose being administeredapproximately 21 hours after the second dose, 3 hours before sampling.All animals were dosed orally by gavage using a dose volume of 10 mL/kg.

Substantial differences in toxicity were observed between the sexes inthe preliminary toxicity test, therefore, in line with currentguidelines the test was performed using both male and female animals.Dose levels of 18.75, 37.5 and 75 mg/kg/day (male animals) and 12.5, 25and 50 mg/kg/day (female animals) were selected. The vehicle controlgroup received purified water and the positive control group for thecomet phase received Ethyl Methanesulfonate at 200 mg/kg. Blood sampleswere taken via the tail vein on Day 3 prior to dosing, at 30 minutes and3 hours post dose from satellite animals and all main study animalsprior to termination.

Cell suspensions from each tissue were obtained from animals in thevehicle control group and in each of the test item groups approximately3 hours after administration of the third dose. Cell suspensions fromanimals in the positive control group were obtained approximately 3hours after a single dose.

Following electrophoresis three slides per animal per tissue wereanalyzed for comets. Slides were visualized by staining with SYBR GOLD®via fluorescence microscopy. 150 morphologically normal cells wereanalyzed for the presence of comets per animal per tissue. DNA strandbreaks were assessed by comparing the mean and median % tail intensities(% TI) from esketamine treated animals compared to vehicle controlvalues. The slides were also examined for any overt toxicity, e.g. anincrease in background debris and/or an increase in the incidence ofexcessively damaged cells (i.e. Hedgehog cells). These cells wereexcluded from the analysis, along with any cells that had unusualstaining artefacts.

Bone marrow smears were obtained from animals in the vehicle control andin each of the test item groups approximately 3 hours afteradministration of the third dose. In addition, slides prepared from aseparate study [CT12GD] from animals treated with Cyclophosphamide awell characterized clastogen, were stained and coded along with the bonemarrow smears prepared from animals in this study.

One smear from each animal was examined for the presence of micronucleiin 4000 polychromatic erythrocytes. The proportion of polychromaticerythrocytes was assessed by examination of at least 1000 erythrocytesfrom each animal. A record of the incidence of micronucleatednormochromatic erythrocytes was also kept.

Statistically significant increases in the median % (TI) were observedin the liver of male Crl:CD(SD) rats administered esketamine at 75mg/kg/day (p<0.001) compared to vehicle control values. The group meanand median % TI values for male animals administered esketamine at 75mg/kg/day were outside of the current vehicle historical control range.Statistically significant increases in the median % TI were observed inthe liver of female Crl:CD(SD) rats administered esketamine at 25 and 50mg/kg/day (p<0.001) compared to vehicle control values. The group meanand median % TI values for female animals administered esketamine at 25and 50 mg/kg/day were outside of the current vehicle historical controlrange.

The positive control compound, Ethyl methanesulphonate, producedsignificant increases in the median % TI when compared to vehiclecontrol values in male and female animals (p<0.001, t-test). No Hedgehogcells were observed in the liver of male or female Crl:CD(SD) ratsadministered esketamine at any dose level, compared to vehicle controlvalues.

Sections of the liver from the vehicle control animals and animalsadministered esketamine at 75 mg/kg/day (male animals) and 25 and 50mg/kg/day (female animals) were processed for histopathologicalexamination and assessed for signs of cytotoxicity, necrosis andapoptosis. Increased hepatocellular mitotic figures were observed somemales animals given 75 mg/kg/day. The macroscopic examination performedafter 3 doses of treatment revealed no test item related lesions.

No statistically significant increases in the frequency ofmicronucleated polychromatic erythrocytes were observed in maleCrl:CD(SD) rats administered esketamine at any dose level compared tovehicle control values. All individual and group mean values were withinthe current vehicle historical control range (control limits).

Statistically significant decreases in the proportion of polychromaticerythrocytes were observed in male Crl:CD(SD) rats administeredesketamine at 37.5 mg/kg/day (pairwise and trend test, p<0.05) and 75mg/kg/day (trend test, p<0.05), compared to vehicle control values. Allindividual and group mean values were within the current vehiclehistorical control range (control limits); therefore this result is notconsidered to be biologically relevant.

No statistically significant increases in the frequency ofmicronucleated polychromatic erythrocytes and no statisticallysignificant decreases in the proportion of polychromatic erythrocyteswere observed in female Crl:CD(SD) rats administered esketamine at anydose level, compared to vehicle control values. All individual and groupmean values were within the current vehicle historical control range(control limits). In accordance with ICH S2(R1) the coded positivecontrol slides prepared from the study CT12GD demonstrated the abilityof the scorer to detect increases in micronucleated polychromaticerythrocytes.

The results of the study indicate that esketamine has shown evidence ofcausing an increase in DNA strand breaks in the liver of male and femaleCrl:CD(SD) rats when administered orally by gavage but has not shown anyevidence of causing an increase in the induction of micronucleatedpolychromatic erythrocytes or bone marrow cell toxicity in male orfemale Crl:CD(SD) rats when administered orally by gavage.

Using PROAST v63.3 (in development), the benchmark dose (BMD50) wasmodelled based on the mean and median tail intensity valuesrespectively, for the male and female rats following exposure toesketamine. The Hill and exponential models provided a suitable fit tothe in vivo comet tail intensity data, which is consistent with thenon-linear dose response. The lower benchmark dose (BMDL50) metrics werecalculated to be 9.83 mg/kg/day in female rats and 27.31 mg/kg/day inmale rats, both using the ‘single slide median Tail Intensity’ whichwere lower and more conservative than those derived when using the‘single slide mean Tail Intensity’. These point of departure (POD)metrics are comparable to the no observed genotoxic effect level forcomet tail intensity in liver at 12.5 mg/kg/day for female and 37.50mg/kg/day for male rats.

Example 3: Repeated dose 28 day toxicokinetic study of esketamine inSprague Dawley rats

The objective of the study was to assess the potential toxicity,neurobehavioral effects, and toxicokinetics (TK) of esketamine whenadministered orally, via gavage, to Sprague Dawley rats for 28 days andto evaluate recovery during a 14-day drug-free period. Fifty male and 50female rats were randomized into 4 groups (15/sex/Groups 1 and 4;10/sex/Groups 2 and 3). Esketamine was administered via oral gavage oncedaily for 28 consecutive days to males at 0 (vehicle control), 6, 10 or30 mg/kg/day and females at 0 (vehicle control), 2, 10 or 20 mg/kg/dayin a dose volume of 10 mL/kg Animals were observed until euthanized andnecropsied on Day 29 (10/sex/group) or 43 (5/sex from Groups 1 and 4).Toxicity was evaluated based on mortality, clinical observations, bodyweights, food consumption, ophthalmology, motor activity, functionalobservational battery, clinical pathology (clinical chemistry,hematology, coagulation and urinalysis), organ weights, anatomic(macroscopic or microscopic) pathology. Toxicokinetic animals(3/sex/Group 1; 6/sex/Groups 2, 3, and 4) were similarly dosed and bledon Day 1 and during Week 4 for toxicokinetic analysis.

There was no mortality found in this study and there were no esketamine-related effects on clinical signs, body weights, food consumption,ophthalmology, motor activity, functional observational battery,clinical pathology or anatomic pathology changes.

Esketamine exposure increased in a generally dose-proportional manner inmales and in a slightly greater than dose-proportional manner in femalesover the dose ranges of 6 to 30 mg/kg/day for males and 2 to 20mg/kg/day for females. After normalization for dose level differences,males had lower exposures than females. Exposures were similar on Day 28compared to Day 1, with the exception of Cmax in females, which washigher on Day 28. The results of the esketamine exposure at day 1 aredescribed in Table 1, and at day 28 in Table 2.

TABLE 1 Dose normal- Esket- ized amine AUC_(0-inf) dose t_(max) C_(max)AUC_(0-t) AUC_(0-inf) (ng*h/ml)/ t_(1/2) Sex (mg/kg) (h) (ng/ml)(ng*h/ml) (ng*h/ml) (mg/kg) (h) F 2 0.17 67.2 57 58 29.0 0.5 F 10 0.17294.9 418 440 44.0 0.7 F 20 0.17 671.8 993 995 49.8 0.9 M 6 0.17 108.799 103 17.2 0.8 M 10 0.17 179.2 175 181 18.1 0.7 M 30 0.17 296.0 580 58519.5 1.2

TABLE 2 Dose normalized Esketamine AUC_(0-inf) dose t_(max) C_(max)AUC_(0-t) (ng*h/ml)/ t_(1/2) Sex (mg/kg) (h) (ng/ml) (ng*h/ml) (mg/kg)(h) F 2 0.17 132.7 62 31.0 NC F 10 0.17 767.9 514 51.3 0.4 F 20 0.171451.1 1064 53.2 0.6 M 6 0.17 113.1 61 10.2 0.6 M 10 0.17 211.3 179 17.90.6 M 30 0.5 398.0 575 19.2 1.5

Example 4 Long Term Carcinogenicity Study

A 104 Week carcinogenicity study of esketamine administered via oralgavage to Sprague Dawley Rats is performed to evaluate the carcinogenicpotential and determine the toxicokinetics of esketamine.

As based on the International Conference on Harmonization (ICH) 51Guidelines S1A, Guideline on the Need for Carcinogenicity Studies ofPharmaceuticals; SIB, Testing for Carcinogenicity of

Pharmaceuticals; and S1C(R2), Dose Selection for Carcinogenicity Studiesof Pharmaceuticals, 236 male and 236 female Sprague Dawley Rats areadministered esketamine over 104 weeks at the doses of 0 (vehiclecontrol), 6, 10 or 30 mg/kg/day for the male rats and 0 (vehiclecontrol), 2, 10 or 20 mg/kg/day for the female rats.

The study end-points include clinical observations, body weight changes,food consumption, bioanalytical toxicokinetic analysis, and anatomicmacroscopic and microscopic pathology findings.

It can thus be demonstrated that the genotoxic changes as shown inExamples 1 and 2 were not identified after 28 days administration atpoint of departure doses and at reduced doses, which factor in an atleast 10 fold safety margin after 730 days, thereby providing a minimalsafe window for chronic esketamine administration.

Example 5 7-Day Forced Swim Test in Male Rats

Groups of, 6 — 7 week old, male Sprague Dawley rats were administeredesketamine by intraperitoneal injection and their behavioral despairassessed by a forced swim test. The animals, in cohorts of 10, wereadministered either a single dose of 15 mg/kg esketamine, 7 daily dosesof either 7.5 or 15 mg/kg esketamine or a vehicle control, and the testperformed 30 minutes after dosing. Statistical evaluation was performedusing an ordinary One-Way ANOVA, t Test and an Uncorrected Fisher's LSDcomparisons test.

Continuous 7-day treatment of esketamine produced strongerantidepressant-like effect than a single acute dose at the same doseslevels. Esketamine at 7.5 and 15 mg/kg, exerted a statisticallysignificant decrease of 40% and 60% respectively in immobility timefollowing chronic treatment, whereas the extent of the effect was lessmarked in acute treated rats (42% of control for 15 mg/kg). Thisindicates that multiple dosing is more effective than a single acutedose of the same dose level and suggests a rationale to treat depressedpatients via a chronic, rather than acute, esketamine regimen.

Example 6 a Single Dose, Rrandomized, Open-Label, Crossover Study inHealthy Volunteers

A randomized, open-label 4-way crossover study in 16 healthy male andfemale subjects was held wherein said subjects were placed in a randomlyassigned order and administered esketamine. Each subject was assigned to1 of 4 treatment sequences according to a randomization code such that 4subjects were assigned to each treatment sequence. There was a wash-outperiod of at least 7 days between dosing periods with doses consistingof either oral or intravenous esketamine hydrochloride. The studyconsisted of an eligibility screening period of 28 days, 4 study periodsinvolving administration of a single dose of esketamine hydrochloridefollowed by safety assessments with blood sampling for PK purposes up to72 hours after study drug administration, discharge at 72 hours afterstudy drug administration and a follow-up visit 7-14 days after the lastPK blood sample was taken on Day 4.

Fifteen of 16 subjects completed the study. One subject (Subject 11)participated in the first treatment period only. This subject waswithdrawn from the study due to an AE of mild hyperbilirubinemia andtherefore did not receive the planned treatments in the 3 remainingtreatment periods. Subject 11 was not included in the PK set, aspresented in Table 3, which therefore included 15 subjects.

TABLE 3 20 mg oral 20 mg oral 100 mg oral 0.3 Parameter Statistic tabletsolution tablet mg/kg iv Esketamine C_(max) (ng/ml) Geometric mean11.92  16.48  65.34   94.50 (CV %) (45%) (48%) (44%) (33%) t_(max) (h)Median 0.75 0.50 0.75  1.00 AUC_(0-t) (ng · h/ml) Geometric mean 20.05 23.44  172.71  249.15 (CV %) (58%) (40%) (51%) (21%) AUC_(0-inf) (ng ·h/ml) Geometric mean 22.46  25.82  180.84  257.14 (CV %) (58%) (39%)(48%) (21%) t_(1/2) (h) Geometric mean 2.84 2.91 7.66  10.16 (CV %)(56%) (37%) (33%) (41%) (S)-norketamine C_(max) (ng/ml) Geometric mean89.73  99.78  351.89   42.25 (CV %) (22%) (26%) (24%) (16%) t_(max) (h)Median 1.00 0.75 1.00  1.25 AUC_(0-t) (ng · h/ml) Geometric mean 418.33 404.96  2267.52   425.96 (CV %) (22%) (19%) (19%) (18%) AUC_(0-inf) (ng· h/ml) Geometric mean 429.05  416.89  2282.91   440.76 (CV %) (22%)(19%) (19%) (18%) t_(1/2) (h) Geometric mean 8.75 8.88 9.27  11.26 (CV%) (28%) (26%) (25%) (28%) (2S,6S)-OH-Norketamine C_(max) (ng/ml)Geometric mean 45.75  46.46  189.32   24.79 (CV %) (33%) (28%) (24%)(28%) t_(max) (h) Median 1.50 1.00 2.00  3.00 AUC_(0-t) (ng · h/ml)Geometric mean 390.10  365.99  1945.85   376.15 (CV %) (27%) (32%) (18%)(28%) AUC_(0-inf) (ng · h/ml) Geometric mean 400.91  377.68  1959.73  389.50 (CV %) (26%) (31%) (18%) (27%) t_(1/2) (h) Geometric mean 7.777.83 8.92  10.68 (CV %) (31%) (30%) (26%) (25%)

Amongst the 15 subjects who completed the study, the treatment wasgenerally well tolerated. A total of 128 TEAEs (treatment-emergentadverse event) were reported by 15 of 16 (94%) subjects of which 79TEAEs reported by 14 of 16 (88%) subjects were to be related to thestudy drug. Overall, a total of 14 of 128 TEAEs reported by 4 (25%)subjects were of moderate severity and 114 of 128 TEAEs reported by 15(94%) subjects were of mild severity. No severe TEAEs or SAEs werereported. The most frequently occurring adverse events (reported morethan twice) were headache, dizziness, hypokinesia, feeling abnormal,fatigue, euphoric mood inappropriate affect, nausea and hyperhidrosis.Table 4 presents the frequency of the most frequently reported relatedTEAEs as a percentage of the subjects that experienced an adverse effectper treatment.

TABLE 4 20 mg oral 20 mg oral 100 mg oral 0.3 TEAE tablet/% solution/%tablet/% mg/kg iv/% Headache — 19 13 19 Dizziness 13  — 13 6 Hypokinesia— — 13 6 Feeling abnormal 7 19 20 13 Fatigue 7 — — 6 Euphoric mood — —13 19 Inappropriate affect —  6 7 6 Nausea — — 20 6 Hyperhidrosis 7 — 7—

Example 7 a Safety, Tolerability, and Pharmacokinetics of Esketamine inMDD Participants Currently Treated with an Antidepressant Drug

An 18 subject in patient study to assess the safety, tolerability, andpharmacokinetics of 40 mg oral esketamine in MDD participants currentlytreated with an antidepressant drug was held. In an, up to, 35 dayscreening phase, the subjects were assessed for study eligibility and,if needed, washed out from disallowed drugs. During this period, it wasalso determined whether the subject's current dose of oralantidepressant medication had been stable for at least 4 weeks. Eligiblesubjects were randomized using a 4:1 allocation scheme to receive either40 mg oral esketamine hydrochloride or placebo once daily, respectively,for 7 days, followed by safety assessments with blood sampling for PKpurposes up to 24 hours after study drug administration. Of the 15subjects which completed the study dosed with esketamine, the meanesketamine C. was found to be 11.82 ng/ml and the mean esketamineAUC_(0-t), 35.62 ng.h/ml.

Example 8 Oral Esketamine Dosage Forms

Oral dosage forms of esketamine hydrochloride are manufactured accordingto the procedures described in WO2016094358, which is incorporated inits entirety, herein, by reference.

The formulation is presented in Table 5.

TABLE 5 60 mg tablet Ingredient (% (w/w)) 32.0% Coated EsketamineGranules 18.75 Coated Polymer Granules 10.04 Mannitol 33.01 Crospovidone20.00 Microcrystalline Cellulose 13.00 Carbomer 2.00 Sodium Bicarbonate2.00 Colloidal silicon Dioxide 0.20 Magnesium stearate 1.00

Example 9 a Dose Range Finding, Multicenter, Double-Randomized,Double-Blind, Placebo-Controlled Phase II study, to determine the safetyand efficacy 50 mg, 65 mg and 80 mg oral esketamine as an adjunctivetherapy in major depressive disorder (MDD) patients with an inadequateresponse to standard anti-depressant therapy

A phase II, dose range finding, multinational, double-randomized,double-blind, placebo-controlled study compares the efficacy, safety andtolerability of once daily 50, 65 or 80 mg oral esketamine to placebotreatment in 204 MDD subjects with inadequate response to antidepressanttherapy. All subjects remain on their current anti-depressant with nodose change during the study.

The study comprises 3 phases, screening (Days 0-28), double-blindtreatment (days 29-56) composed of two 2-week periods (period 1, period2) and post-treatment safety follow-up (days 57 — 70) following the laststudy treatment administration.

During screening, subjects are assessed for study eligibility and washedout from disallowed drugs. After being found eligible, subjects arerandomized at the beginning of Period 1 using a 3:1:1:1 allocationscheme to receive, once daily, either placebo or 50 mg, 65 mg, or 80 mgoral esketamine, respectively. At the conclusion of period 1, allsubjects are blindly assessed for response based on their change inMADRS-10 score from baseline to week 2. Subjects who received placeboduring period 1 are re-randomized using a 1:1:1:1 allocation scheme toreceive in the 2 weeks (period 2) either placebo or 50 mg, 65 mg or 80mg oral esketamine once daily, respectively. The re-randomization isstratified by the placebo response in Period 1 (Change in MADRS <or >50%and MADRS score <or >18). Subjects that were on oral esketamine inperiod 1 remain on the drug at the same dosage for the 2 weeks of period2.

Subjects receive the first dose of their study drug at the study siteand are then closely monitored for 3 hours to assess for potentialneuropsychiatric adverse events using a comprehensive set of scales toidentify sleepiness, sedation and dissociative effects. Thereafter, thesubject is provided with a 1 week supply of the study drug foradministration at their place of residence and instructed to take thestudy drug in the evening (except at the day of the weekly visit when itis taken at the study site) and not to drive until the next morning. Atevery subject visit, a psychiatrist evaluates the subject's MADRS-10score.

The study's primary efficacy endpoint is the change from baseline toweek 2 (in the 2 periods) in 10 items Montgomery—Asberg DepressionRating Scale (MADRS-10).

Secondary efficacy endpoints include the change from baseline Sheehandisability scale (SDS) at 2 weeks, remission rate at 2 weeks (MADRS-10<10), responder rate at 2 weeks (>50% improvement in MADRS-10), changefrom baseline in self-rated Symptoms of Depression Questionnaire (SDQ)at 2 weeks, physician administered Clinical Global ImpressionImprovement (CGI-I) at 2 weeks and the change from baseline in Physicianadministered Clinical Global Impression Severity (CGI-S) at 2 weeks.

Exploratory Endpoints include the change from baseline in GeneralizedAnxiety Disorder 7 items scale (GAD-7) at 2 weeks and the change frombaseline to week 4 in Montgomery—Asberg Depression Rating Scale(MADRS-10) for the subset of subjects receiving the same study drug forthe 4 weeks.

Safety and tolerability endpoints include adverse events, hematology,biochemistry and urinalysis, immunological parameters, physicalexamination findings, blood pressure and heart rate every 30 minutes forthe 3 hours following study drug administration, 12 lead ECG findings,withdrawal rates, Digit Symbol Substitution Test (DSST), reaction timetest (Cambridge COGNITION), self-administered Stanford sleepiness scale,a Bladder Pain/Interstitial Cystitis Symptom Score (BPIC-SS), a ModifiedObserver's Alertness/Sedation Scale (MOAA/S), a Clinician-AdministeredDissociative States Scale (CADSS), a suicidality scale-Clinician-RatedColumbia Suicide Severity Rating Scale (C-SSRS), 4 items positivesymptoms subscale from the Brief Psychiatric Rating Scale (BPRS) and 20item Physician Withdrawal Checklist (PWC-20) during the follow-upperiod.

Those skilled in the art will appreciate that numerous changes andmodifications can be made to the preferred embodiments of the disclosureand that such changes and modifications can be made without departingfrom the spirit of the disclosure. It is, therefore, intended that theappended claims cover all such equivalent variations as fall within thetrue spirit and scope of the disclosure.

1. A method of treating major depressive disorder (MDD) in a humanpatient in need thereof comprising orally administering to said patientan oral dosage form comprising between about 41 mg and about 80 mg ofesketamine over a treatment regimen of at least 28 days and wherein theesketamine C_(max) of said administration is 30 ng/ml or less and/or theesketamine AUC_(0-t) of said administration is 60 ng*h/ml or less. 2.The method of claim 1, wherein the oral dosage form comprises about 45mg of esketamine.
 3. The method of claim 1, wherein the oral dosage formcomprises about 50 mg of esketamine.
 4. The method of claim 1, whereinthe oral dosage form comprises about 55 mg of esketamine.
 5. The methodof claim 1, wherein the oral dosage form comprises about 60 mg ofesketamine.
 6. The method of claim 1, wherein the oral dosage formcomprises about 65 mg of esketamine.
 7. The method of claim 1, whereinthe oral dosage form comprises about 70 mg of esketamine.
 8. The methodof claim 1, wherein the oral dosage form comprises about 75 mg ofesketamine.
 9. The method of claim 1, wherein the oral dosage formcomprises about 80 mg of esketamine.
 10. The method of claim 1, whereinthe treatment regimen is between 28 days and about 730 days.
 11. Themethod of claim 10, wherein the treatment regimen is between 28 days andabout 365 days.
 12. (canceled)
 13. The method of claim 1, wherein theadministration is once daily over the treatment regimen.
 14. The methodof any of claim 1, wherein the administration is intermittent over thetreatment regimen.
 15. The method of claim 14, wherein theadministration is once every second day to once a month over thetreatment regimen.
 16. (canceled)
 17. (canceled)
 18. (canceled)
 19. Theadministration of claim 14, wherein the frequency of the administrationvaries over the treatment regimen.
 20. The method of claim 1, whereinthe treatment regimen results in a reduction of the symptoms of majordepressive disorder (MDD) after at least 28 days of treatment.
 21. Themethod of claim 1, further comprising the administration of a secondmedication other than (R)-ketamine.
 22. The method of claim 21, whereinthe second medication is an antidepressant, an antimanic agent, or ananxiolytic drug.
 23. The method of claim 22, wherein the antidepressantis selected from the group consisting of fluoxetine, sertraline,paroxetine, citalopram, escitalopram, venlafaxine, desvenlafaxine,duloxetine, and fluvoxamine.
 24. (canceled)
 25. (canceled) 26.(canceled)
 27. (canceled)
 28. (canceled)
 29. (canceled)
 30. The methodof claim 1, wherein the esketamine is esketamine hydrochloride.